Diagsheet

2020 Hyundai Sonata · symptom sheet

Check engine light or misfire

  • 25owner reports
  • 47,000median miles
  • 0involved a crash

Newest report Jul 10, 2026 · checked Sep 9, 2026

111 of the 178 complaints on this car are about the engine. 25 of those describe misfire, which makes it the most reported problem on the 2020 Sonata.

Tick what matches of 25 reports

4
2
9

What got replaced

Owners who name the part that was replaced mention the sensor (3 reports).

Recalls and investigations

2 recalls on the engine cover the 2020 model year. A recall on the same system isn't always the same failure, so read the defect text.

25V-796Nov 18, 2025
Fuel System, Gasoline

Hyundai Motor America (Hyundai) is recalling certain 2020-2023 Sonata vehicles. A damaged check valve can allow air to enter the fuel tank, causing it to expand and contact hot exhaust components, melting the tank.

Risk and remedy
Risk: A melted fuel tank can leak, increasing the risk of a fire.
Remedy: Dealers will inspect and replace the check valve. The fuel tank assembly will be inspected for damage and replaced if necessary. Additionally, dealers will inspect and update the engine control unit software. All repairs will be performed as necessary, free of charge. Owner notification letters were mailed beginning March 13, 2026. Owners may contact Hyundai customer service at 1-855-371-9460. Hyundai's number for this recall is 286. Vehicle Identification Numbers (VINs) involved in this recall became searchable on NHTSA.gov on November 19, 2025.
20V-213Apr 9, 2020
Electrical System:Software

Hyundai Motor America (Hyundai) is recalling certain 2020 Nexo and Sonata vehicles. The Remote Smart Parking Assist (RSPA) software may fail to prevent vehicle movement upon detection of an RSPA system malfunction.

Risk and remedy
Risk: Unintended vehicle movement increases the risk of a crash.
Remedy: Hyundai will notify owners, and dealers will reprogram the RSPA software, free of charge. The recall began June 3, 2020. Owners may contact Hyundai customer service at 1-855-371-9460. Hyundai's number for this recall is 191.

NHTSA investigations into the engine on the Sonata

DP22-003opened Sep 12, 2022
Engine · model years 2006 to 2021

Loss of motive power. Closed dec 12, 2023.

NHTSA summary
The National Highway Traffic Safety Administration (NHTSA) received a letter dated July 13, 2022, petitioning the Agency to initiate a safety defect investigation into loss of motive power allegations attributed to oil drain pan assembly failures on certain Hyundai Motor America, Inc. and Kia America, Inc. vehicles spanning Model Years (MY) 2005-2021. The Petitioners cited examples of complaints indicating that the subject vehicles were experiencing rapid loss of engine oil due to oil drain plug back outs, resulting in loss of motive power and/or catastrophic engine damage. Additional complaints were provided which alleged that the oil drain pans lack sufficient structural integrity and are susceptible to cracking. The petition itself can be reviewed at NHTSA.gov under ODI number 11481745. On September 12, 2022, the Office of Defects Investigation (ODI) opened Defect Petition (DP22-003) to evaluate the Petitioners’ request. The Petitioners have provided additional complaints within four supplemental letters dated January 31, 2023, March 21, 2023, May 23, 2023, and August 4, 2023. ODI’s evaluation included the review and analysis of the complaints and supporting information submitted by the Petitioners, as well as additional complaints submitted directly to NHTSA which referenced either the oil drain plug or a crack in the oil pan. After reviewing the available data, ODI has not identified evidence that would support opening a defect investigation into the oil drain pan as
EA21-003opened Dec 22, 2021
Engine · model years 2011 to 2016

Engine fires. Closed feb 5, 2024, led to recall 23V-877.

NHTSA summary
On March 29, 2019, the Office of Defects Investigation (ODI) opened two Preliminary Evaluations (PE19-003 on Hyundai and PE19-004 on Kia) to broadly investigate incidents of non-crash fires (regardless of origin or operational status of the vehicle) on various model year Hyundai and Kia vehicles. During the PE investigations, Hyundai and Kia issued several recalls to address vehicle fires, including those due to engine failures involving various engine types. The remedies for the engine failure recalls typically involve engine inspection (to detect existing damage), and if necessary, engine replacement. Additionally, both manufacturers have been installing an engine control software modification known as Knock Sensor Detection Software (KSDS) which is intended to detect impending engine failure, alert the driver, and limit engine power (to lessen likelihood of engine failure).KSDS is being installed under recalls and non-safety field actions, and both companies have extended limited engine warranties (see recall files). On December 22, 2021, ODI upgraded PE19-003 and PE19-004 to this Engineering Analysis (EA21-003, covering both Hyundai and Kia) to evaluate the scope of the prior recalls related to engine failures/fires and the efficacy of the recall remedies for the recalls, as well as the long-term viability of related programs and non-safety field actions being conducted by Hyundai and Kia. The former issue involved approximately 550,000 MY 2013 Hyundai Elantra, MY
PE19-003opened Mar 29, 2019
Electrical · model years 2011 to 2014

Non-crash vehicle fires. Closed dec 22, 2021, led to recall 20V-061.

NHTSA summary
During this Preliminary Evaluation (PE), the Office of Defects Investigation (ODI) assessed the scope, frequency and potential safety-related consequences of non-crash vehicle fires caused by both engine failures and failures of other vehicle systems/components in model year (MY) 2011-2014 Hyundai Sonata and Santa Fe vehicles equipped with Theta II and Lambda II engines (approximately 1.3 million vehicles). ODI also reviewed field data of other Hyundai vehicles equipped with Theta II, Gamma, Nu and Lambda engines (approximately 4.8 million). As a result of this PE, Hyundai has issued NHTSA Recalls 20V-746 and 21V-727 to address potential engine failures and fires in certain Hyundai vehicles equipped with various engine types. Additional information on these and other related recall actions is available in the downloadable version of this resume available at NHTSA.gov. In addition, ODI has upgraded this PE to an Engineering Analysis (EA) 21-003 which will focus on potential recall scope concerns and recall remedy concerns related to the engine failure rewlated recalls mentioned above and conducted previously. See the EA21-003 Opening Resume available at NHTSA.gov for more information. Also available in the downloadable version of this resume is a list of the reference numbers for the 302 ODI reports, or Vehicle Owner Questionnaires (VOQs), cited above which ODI received through mid-November 2021. Note that the Manufacturer reports cited above are customer complaints received t
DP18-003opened Aug 21, 2018
Electrical · model years 2011 to 2014

Non-crash vehicle fires. Closed may 10, 2019, led to recall 18V-907.

NHTSA summary
In a letter dated June 11, 2018, the Center for Auto Safety (CAS) petitioned the National Highway Traffic Safety Administration (NHTSA) to initiate a safety defect investigation into non-collision related fires on model year (MY) 2011-2014 Kia Optima and Sorento, and Hyundai Sonata and Santa Fe vehicles. In a letter dated July 24, 2018, CAS requested that MY 2010-2015 Kia Soul vehicles be added to the petition. CAS stated that there is a higher number of complaints to NHTSA regarding non-crash fires on these vehicles compared to other similar vehicles. The Office of Defects Investigation (ODI) had already opened Recall Queries (RQ17-003 and RQ17-004) on all Kia and Hyundai vehicles equipped with Theta II engines for engine failures that may cause stalling and fires.The queries cover most of the petition subject Optima, Sorento, Sonata, and Santa Fe vehicles but not any of the subject Soul vehicles.On August 21, 2018, ODI opened a Defect Petition (DP18-003) to evaluate whether to grant or deny the CAS petition. ODI sent Information Request letters to Kia and Hyundai (September and October 2018) requesting information on all engine and non-engine related fires in the petition vehicles.ODI performed extensive analysis on the information obtained from Kia and Hyundai. During the DP18-003 analysis, Kia and Hyundai each initiated three additional safety recalls related to engine compartment fires on certain petitioned and non-petitioned vehicles (nearly 740,000 total vehicles: Reca
RQ17-004opened May 18, 2017
Engine · model years 2011 to 2014

Scope and timeliness. Closed dec 22, 2021, led to recall 17V-226.

NHTSA summary
NHTSA opened Recall Query (RQ) 17-004 to investigate the timeliness and scope of Hyundai?s Theta II GDI engine recalls (Recall Nos. 15V-568 and 17V-226), and Hyundai?s compliance with reporting requirements. On November 23, 2020, the Agency entered into a Consent Order with Hyundai to administratively resolve NHTSA?s assertions of violations of law in connection with RQ17-004. NHTSA?s assertions included that Hyundai may be liable for civil penalties on multiple grounds, including the untimeliness of Recall Nos. 15V-568 and 17V-226, inaccuracies in Hyundai?s recall reports, and that a required report describing potential safety-related issues contained certain inaccuracies or omissions.Under the Consent Order, Hyundai agreed to a total civil penalty of $140,000,000. The total civil penalty included payment of $54,000,000 as a Non-Deferred Amount. Hyundai also agreed to a sum of $46,000,000 as an Abeyance Amount to be deferred and held in abeyance pending its satisfactory completion, as reasonably determined by NHTSA, of the requirements of the Consent Order.Additionally, Hyundai agreed to a $40,000,000 Performance Obligation Amount to be expended by Hyundai to fulfill specified Safety Data Analytics Infrastructure obligations and Test and Inspection Laboratory obligations. The Consent Order also includes other terms designed to enhance Hyundai?s safety practices, and requires Hyundai to retain a Third-Party Auditor who directly reports to NHTSA.Other than RQ17-004, the Consen
PE94-043opened May 27, 1994
Electrical · model years 1986 to 1991

Charging system failures. Closed oct 31, 1994.

NHTSA summary
There is no summary currently available

When it happens

The middle half of failures fell between 3,500 and 82,000 miles, from the 10 reports that gave a mileage.

120
121
122
123
1024
825
326

What owners wrote

No report on this problem is short enough to quote in full.

Should you keep driving it?

This page can't tell you that. 0 of 25 reports involved a crash. Owners who file are the ones who had a bad experience, and nobody checks their reports. If the problem affects steering, braking, power or a fire risk, treat it as a safety fault and have it inspected before a long or high-speed drive.

File your own report with NHTSA. Complaint counts are how a problem gets an investigation.